多离子空间等离子体中快磁声波与粒子的回旋共振特性
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摘要
快磁声波是空间等离子体中一种接近垂直传播的右旋极化电磁波,能够在等离子体层内外传播.快磁声波与带电粒子的回旋共振相互作用能够导致高能电子随机加速和投掷角扩散、能量质子投掷角扩散等,从而影响辐射带高能带电粒子的动态过程,分别基于完整的色散关系和高密度近似的色散关系,在不同空间等离子体条件下研究多离子空间等离子体中不同传播角的快磁声波色散曲线,并计算了快磁声波与H~+,He~+和O~+离子的最小共振能量.结果表明,当传播角较小时,采用高密度近似与采用完整色散关系计算的离子最小共振能量没有太大差别.在中低密度中强磁场空间等离子体中,传播角≥88°时高密度近似色散关系会带来很大的误差,因此应利用完整色散关系计算最小共振能量.
Fast Magnetosonic(MS) waves are right-hand polarized waves. They propagate both inside and outside the plasmasphere, and the wave vectors are almost perpendicular to the ambient magnetic field. Fast MS waves can lead to local electron acceleration,scattering of outer radiation belt energetic electrons, and scattering of energetic protons etc. Using the fully and high-density approximated dispersion relations, the dispersion curve of fast MS with different wave normal angle is analyzed, and the minimum resonant energy between MS waves and ions(H+, He+, and 0+) are calculated. The results show that, as the wave normal angle is relatively small, the minimum resonant energy obtained by the high-density approximated and fully dispersion relation is quite close to each other in a high density and weak magnetic field space plasma. Remarkable error occurs when the high-density approximated dispersion relation is used in the low and medium density space plasma or when the wave normal angle is greater than 88°. Therefore, the fully dispersion relation must be used in these cases.
Fast Magnetosonic(MS) waves are right-hand polarized waves. They propagate both inside and outside the plasmasphere, and the wave vectors are almost perpendicular to the ambient magnetic field. Fast MS waves can lead to local electron acceleration,scattering of outer radiation belt energetic electrons, and scattering of energetic protons etc. Using the fully and high-density approximated dispersion relations, the dispersion curve of fast MS with different wave normal angle is analyzed, and the minimum resonant energy between MS waves and ions(H+, He+, and 0+) are calculated. The results show that, as the wave normal angle is relatively small, the minimum resonant energy obtained by the high-density approximated and fully dispersion relation is quite close to each other in a high density and weak magnetic field space plasma. Remarkable error occurs when the high-density approximated dispersion relation is used in the low and medium density space plasma or when the wave normal angle is greater than 88°. Therefore, the fully dispersion relation must be used in these cases.
引文
[1]RUSSELL C T,HOLZER R E,SMITH E J.OGO 3 observations of ELF noise in the magnetosphere:2.The nature of the equatorial noise[J].J.Geophys.Res.,1970,75(4):755-768
[2]PERRAUT S,ROUX A,ROBERT P,et al.A systematic study of ULF waves above F_(H+)from GEOS 1 and 2 measurements and their relationships with proton ring distributions[J].J.Geophys.Res.,1982,87(A8):6219-6236
[3]NEMEC F,SANTOLIK O,GEREOVA K,et al.Initial results of a survey of equatorial noise emissions observed by the Cluster spacecraft[J].Planet.Space Sci.,2005,53(1-3):291-298
[4]TSURUTANI B T,FALKOWSKI B J,PICKETT J S,et al.Extremely intense ELF magnetosonic waves:a survey of polar observations[J].J.Geophys.Res.,2014,119(2):964-977
[5]POKHOTELOV D,LEFEUVRE F,HORNE R B,et al.Survey of ELF-VLF plasma waves in outer radiation beltobserved by Cluster STAFF-S A experiment[J].Ann.Geophys.,2008,26(11):3269-3277
[6]MEREDITH N P,HORNE R B,ANDERSON R R.Survey of magnetosonic waves and proton ring distributions in the Earth's inner magnetosphere[J].J.Geophys.Res.,2008,113(A6):A06213
[7]ZHOU Meng,NI Binbin,HUANG Shiyong,et al.Observation of large-amplitude magnetosonic waves at dipolarization fronts[J].J.Geophys.Res.,2014,119(6):4335-4347
[8]CURTIS S A,WU C S.Gyroharmonic emissions induced by energetic ions in the equatorial plasmasphere[J].J.Geophys.Res.,1979,84(A6):2597-2607
[9]LIU Kaijun,GARY S P,WINSKE D.Excitation of magnetosonic waves in the terrestrial magnetosphere:particle-in-cell simulations[J].J.Geophys.Res.,2011,116(A7):A07212
[10]CHEN Lunjin,THORNE R M,JORDANOVA V K,et al.Global simulation of magnetosonic wave instability in thestorm time magnetosphere[J].J.Geophys.Res.,2010,115(A11):A11222
[11]XIAO Fuliang,ZHOU Qinghua,HE Zhaoguo,et al.Three-dimensional ray tracing of fast magnetosonic waves[J].J.Geophys.Res.,2012,117(A6):A06208
[12]XIAO Fuliang,ZHOU Qinghua,HE Yihua,et al.Penetration of magnetosonic waves into the plasmasphere observed by the Van Allen Probes[J].Geophys.Res.Lett.,2015,42(18):7287-7294
[13]ZHOU Qinghua,XIAO Fuliang,YANG Chang,et al.Excitation of nightside magnetosonic waves observed by Van Allen Probes[J].J.Geophys.Res.,2014,119(11):9125-9133
[14]HORNE R B,THORNE R M,GLAUERT S A,et al.Electron acceleration in the Van Allen radiation belts by fast magnetosonic waves[J].Geophys.Res.Lett.,2007,34(17):L17107
[15]BORTNIK J,THORNE R M.Transit time scattering of energetic electrons due to equatorially confined magneto-sonic waves[J].J.Geophys.Res.,2010,115(A7):A07213
[16]LI Jinxing,NI Binbin,XIE Lun,et al.Interactions between magnetosonic waves and radiation belt electrons:comparisons of quasi-linear calculations with test particle simulations[J].Geophys.Res.Lett.,2014,41(14):4828-4834
[17]HORNE R B,WHEELER G V,ALLEYNE H S C K.Proton and electron heating by radially propagating fast magnetosonic waves[J].J.Geophys.Res.,2000,105(A12):27597-27610
[18]XIAO Fuliang,ZONG Qiugang,WANG Yongfu,et al.Generation of proton aurora by magnetosonic waves[J].Sci.Rep.,2014,4:5190
[19]XIAO Fuliang,YANG Chang,SU Zhengpeng,et al.Wave-driven butterfly distribution of Van Allen belt relativistic electrons[J].Nat.Commun.,2015,6:8590
[20]STIX T H.Waves in Plasmas[M].New York:American Institute of Physics,1992:56-57
[21]LYONS L R.Pitch angle and energy diffusion coefficients from resonant interactions with ion-cyclotron and whistler waves[J].J.Plasma Phys.,1974,12(3):417-432
[22]ALBERT J M.Evaluation of quasi-linear diffusion coefficients for whistler mode waves in a plasma with arbitrary density ratio[J].J.Geophys.Res.,2005,110(A3):A03218
[23]SUMMERS D.Quasi-linear diffusion coefficients for fieldaligned electromagnetic waves with applications to the magnetosphere[J].J.Geophys.Res.,2005,110(A8):A08213
[2]PERRAUT S,ROUX A,ROBERT P,et al.A systematic study of ULF waves above F_(H+)from GEOS 1 and 2 measurements and their relationships with proton ring distributions[J].J.Geophys.Res.,1982,87(A8):6219-6236
[3]NEMEC F,SANTOLIK O,GEREOVA K,et al.Initial results of a survey of equatorial noise emissions observed by the Cluster spacecraft[J].Planet.Space Sci.,2005,53(1-3):291-298
[4]TSURUTANI B T,FALKOWSKI B J,PICKETT J S,et al.Extremely intense ELF magnetosonic waves:a survey of polar observations[J].J.Geophys.Res.,2014,119(2):964-977
[5]POKHOTELOV D,LEFEUVRE F,HORNE R B,et al.Survey of ELF-VLF plasma waves in outer radiation beltobserved by Cluster STAFF-S A experiment[J].Ann.Geophys.,2008,26(11):3269-3277
[6]MEREDITH N P,HORNE R B,ANDERSON R R.Survey of magnetosonic waves and proton ring distributions in the Earth's inner magnetosphere[J].J.Geophys.Res.,2008,113(A6):A06213
[7]ZHOU Meng,NI Binbin,HUANG Shiyong,et al.Observation of large-amplitude magnetosonic waves at dipolarization fronts[J].J.Geophys.Res.,2014,119(6):4335-4347
[8]CURTIS S A,WU C S.Gyroharmonic emissions induced by energetic ions in the equatorial plasmasphere[J].J.Geophys.Res.,1979,84(A6):2597-2607
[9]LIU Kaijun,GARY S P,WINSKE D.Excitation of magnetosonic waves in the terrestrial magnetosphere:particle-in-cell simulations[J].J.Geophys.Res.,2011,116(A7):A07212
[10]CHEN Lunjin,THORNE R M,JORDANOVA V K,et al.Global simulation of magnetosonic wave instability in thestorm time magnetosphere[J].J.Geophys.Res.,2010,115(A11):A11222
[11]XIAO Fuliang,ZHOU Qinghua,HE Zhaoguo,et al.Three-dimensional ray tracing of fast magnetosonic waves[J].J.Geophys.Res.,2012,117(A6):A06208
[12]XIAO Fuliang,ZHOU Qinghua,HE Yihua,et al.Penetration of magnetosonic waves into the plasmasphere observed by the Van Allen Probes[J].Geophys.Res.Lett.,2015,42(18):7287-7294
[13]ZHOU Qinghua,XIAO Fuliang,YANG Chang,et al.Excitation of nightside magnetosonic waves observed by Van Allen Probes[J].J.Geophys.Res.,2014,119(11):9125-9133
[14]HORNE R B,THORNE R M,GLAUERT S A,et al.Electron acceleration in the Van Allen radiation belts by fast magnetosonic waves[J].Geophys.Res.Lett.,2007,34(17):L17107
[15]BORTNIK J,THORNE R M.Transit time scattering of energetic electrons due to equatorially confined magneto-sonic waves[J].J.Geophys.Res.,2010,115(A7):A07213
[16]LI Jinxing,NI Binbin,XIE Lun,et al.Interactions between magnetosonic waves and radiation belt electrons:comparisons of quasi-linear calculations with test particle simulations[J].Geophys.Res.Lett.,2014,41(14):4828-4834
[17]HORNE R B,WHEELER G V,ALLEYNE H S C K.Proton and electron heating by radially propagating fast magnetosonic waves[J].J.Geophys.Res.,2000,105(A12):27597-27610
[18]XIAO Fuliang,ZONG Qiugang,WANG Yongfu,et al.Generation of proton aurora by magnetosonic waves[J].Sci.Rep.,2014,4:5190
[19]XIAO Fuliang,YANG Chang,SU Zhengpeng,et al.Wave-driven butterfly distribution of Van Allen belt relativistic electrons[J].Nat.Commun.,2015,6:8590
[20]STIX T H.Waves in Plasmas[M].New York:American Institute of Physics,1992:56-57
[21]LYONS L R.Pitch angle and energy diffusion coefficients from resonant interactions with ion-cyclotron and whistler waves[J].J.Plasma Phys.,1974,12(3):417-432
[22]ALBERT J M.Evaluation of quasi-linear diffusion coefficients for whistler mode waves in a plasma with arbitrary density ratio[J].J.Geophys.Res.,2005,110(A3):A03218
[23]SUMMERS D.Quasi-linear diffusion coefficients for fieldaligned electromagnetic waves with applications to the magnetosphere[J].J.Geophys.Res.,2005,110(A8):A08213